Abkhazia and Georgia have been in a state of frozen conflict since 1993, when Abkhaz troops succeeded in driving the Georgian army out of their semi-autonomous province - but the temperature is rising quickly.

Both sides accuse the other of carrying out air raids on Monday, and while the Abkhaz authorities have started mobilising reservists, the Georgian authorities have threatened to retaliate.

Just as in the war of 1992-1993, Russian and Chechen forces risk becoming involved, if they are not already.

Georgia says a helicopter that bombed three Georgian-inhabited villages inside Abkhazia came from Russia, while the self-declared Abkhaz Government says Chechen rebels and Georgian fighters recently moved into the province from the east.

Guerrillas

The situation is further confused by the presence of Georgian guerrillas, who attack Abkhaz targets without government backing - although the authorities in Tbilisi have often been accused of doing little to stamp them out. They are openly sponsored by the pro-Georgian Abkhaz government in exile.

These guerrillas have usually operated in the southernmost part of Abkhazia - the Gali region - but now the Abkhaz authorities say Georgian fighters are present, along with Chechen fighters, in the lawless Kodori Gorge.

After eight years of half-hearted attempts to reach a political settlement - and deadlock for most of that time - it would not take much to tip Abkhazia back into war

It was here that a helicopter carrying UN monitors was apparently shot down on Monday, with the loss of nine lives. No-one knows who did it.

During the 1992-1993 conflict - which began after Georgian troops attempted to use armed force to halt Abkhaz moves towards independence - Chechens and other North Caucasian peoples rushed to the aid of the Abkhaz.

Abkhaz Foreign Minister Sergei Shamba says Russian Cossacks have already offered their support this time too. However, since 1993, Russia and Chechnya have been at blows (except for the period from 1996-1999), and Abkhazia's main priority has been to preserve good relations with Moscow rather than the Chechen rebel leaders.

Abkhaz forces now accuse Chechen guerrillas of taking part in a raid on an Abkhaz village, in which 14 people were killed. They say they have succeeded in surrounding the guerrillas in the Kodori Gorge and are now destroying them.

Suspected leader

It is thought the Chechens may be a group led by the command of a well-known Chechen field commander, Ruslan Gelayev, who was earlier reported to have been taking refuge inside Georgia, in an area near the Chechen border - the Pankisi Gorge - inhabited by ethnic Chechens.

One theory is that he and his men sought to take refuge in Abkhazia after Georgia came under increasing Russian pressure to expel the Chechens from the Pankisi Gorge - and after vague threats from Russian officials to launch a cross-border offensive into Georgia.

The Georgian army, and at least one prominent Georgian guerrilla leader, say they have not been involved in the latest clashes.

However, their presence near the borders of Abkhazia adds to the tinderbox atmosphere. Many Georgians long to see their army's 1993 defeat avenged.

Moscow suspected

Any Georgian intervention, in retaliation for the helicopter raid for example, could trigger a Russian response. Russian aircraft supported Abkhaz fighters eight years ago, and Georgians suspect Moscow of orchestrating the entire war.

Russian officials say they are watching the situation closely. They have a peacekeeping force, which is meant to separate the two sides, and a military base in Abkhazia which could be re-occupied by paratroopers who were formerly based there at a moment's notice.

After eight years of half-hearted attempts to reach a political settlement - and deadlock for most of that time - it would not take much to tip Abkhazia back into war.